However, I don't think anything like this should be included in Bitcoin. Although not any more dangerous than "firstbits", it would make it too easy to spoof people into sending money to an "amazon.com" that goes to a malicious squatter instead. It also hinders anonymity and the sender identification that comes with one-time-use addresses.
I agree with your point about anonymity, and I am sure there are other equally good reasons not to include such a thing in bitcoin (for instance, it would make it that much more complicated to prune the blockchain to keep db size down if that were to be implemented in the future), but for bitcoin to survive and thrive as the main cryptocurrency (should cryptocurrencies actually survive and thrive at all), it would need to do whatever the "customers" demand. IOW, the reasons all become moot if said thing is in demand and you don't want bitcoin to fall by the wayside. Regarding the "amazon.com" example, that can happen as it stands now, with a website hack, DNS and SSL hacks, or spoofing, and it can cost a user who didn't pay with credit card dearly. In the future, someone might insure bitcoin transactions the way credit card transactions are insured, so between all of these points, I'm not sure it holds much water.